Selector switch



y 1953 G. A. KWASNIEWSKI 2,639,338

SELECTOR SWITCH Filed June 5, 1951 IN VEN TOR.

Geome- A. KWASNIEWSKI F/5; 4 BY ATTORNEY parts Patented May 19, 1953 SELECTOR SWITCH George A. Kwasniewski, Moundview Township,

Ramsey County,

Minn., assignor to Minneapolis-Honeywell Regulator Company,

Minneapolis, Minn., a corporation of Delaware Application June 5, 1951, Serial No. 230,055

. 9 Claims.

This invention is directed to a switch having a plurality of sets of contacts with an interlock between sets to correlate their operation under certain conditions. 7

One object of the invention is to provide a switching mechanism having two sets of contacts with an interlock that determines the position of one set at a predetermined position or positions of the other set.

Another object is to provide a switching mechanism in which one set of contacts is moved between a plurality of positions by rotation of a member and another set of contacts is actuated by a second member slidably axially in the first member. Under one phase of the invention the position of the second set of contacts will be correlated. with the position of the first set at one or more positions of the first set. A broader object is to provide a mechanism in which the opcrative position of two control means of any type are correlated under certain conditions.

A still further object is to provide a switch mechanism wherein two normally manually operable switches are moved to predetermined positions under certain conditions of a third switch.

Other objects will be apparent from the following specification and claims, and from the drawing, in which:

Figure 1 is an elevation of the panel of the se lector switch-as it appears to the operator;

Figure 2 is an elevation of the selector switch as seen from the right of Figure 1;

Figure 3 is an elevation of the same aspect as Figure 1 control knobs removed, and with the operative in the same position as in Figure 1;

Figure 4 ha sectional view taken on line 4-4 of Figure 3 and with the switch turned to the Glide position; and

Figure 5 is a fragmentary section taken on line 55 of Figure 3, with the switch turned to the Glide position.

The illustrative embodiment of the invention is a function. selector switch used in an airplane to tie the automatic approach system into the autopilot system so that the airplane will be guided in accordance with a radio landing approach beam. In the Outbound and Inbound positions, the radio beam controls only the horizontal direction of the airplane, while in the Glide position the altitude of the airplane, is also controlled. In order to prevent excessive deviations from the desired course, as might be caused by changing cross wind, a directional gy roscope signal may be added to the radio signal so that changes in heading will be sensed and corrected before the airplane is actually off the bea The ccn tmct on of the switch is such switch in the but with the panel and that the gyroscope signal is optionally available in the "Inbound and Outbound positions, but is positively included in the Glide position. An additional manual switch controlling available engine power is also positively moved to its high power position when the selector switch is turned to Glide.

Figures 1 and 2 show a portion of a panel In which also carries other controls for an automatic approach coupler with which the present invention is not concerned. A channel shaped frame H is suitably secured to the backside of the panel l0 and carries the several elements of the switching mechanism. As seen in Figure 2, a two section rotary tap switch M is secured to the rear surface of the frame H. The tap switch I4 includes a drive shaft 15 that extends through the frame l| toward the panel Ill. The switch M includes a detent mechanism comprising a stationary member |=6 having a plurality of raised and lowered portions with which 'a pair of balls H are adapted to engage. The balls I! are carried by a flexible strip l 8 rotatable with the shaft l5 so that the shaft will tend to stop only in positions corresponding to operative positions of the tap switch. The rotary tap switch is of con- Ventional commercially available construction and it is not believed necessary to describe it in detail. A tube 2| is secured to the end of the shaft [5 and extends outwardly through the panel HI, and a knob 22 is secured thereto by a set crew 23 so that the rotary tap switch I4 maybe angularly positioned from the front face of the panel l0. Suitable stop means, not shown, is provided in the tap switch M to limit rotation of the knob 22 to the indicated positions of Outbound and Glide, as indicated in Figure 1.

As seen in Figures 2 and 3, the frame I carries a snap switch 25 having an actuating button 26 which, when depressed, is adapted to close the circuit through the switch to provide the gyroscope control function mentioned above. The details of the internal construction of the switch 25 have no bearing on the present invention and are therefore not shown in detail. As shown most clearly in Figure 4, a sleeve 28 is carried by the tube 2| and is axially slidable thereon. A rod 29 is carried within the tube 2| and is connected to the sleeve 28 by a pin 30 which extends through slots 3| in the tube 2 I. It will 'be seen, therefore, that the sleeve 28 and rod 29 will rotate with the tube 2| but may be axially displaced with respect thereto by movement of the pin 30 in the slot 3|. A knob 33 carried on the end of rod 29 and disposed on the outer surface of the knob 22 is available for manually displacing the sleeve 28 when the knob 22 is in either the Outbound or Inbound positions. A circular disc 35, integral with the sleeve 28, has a rounded periphery adapted to engage the actuating button 26 of the snap switch 25 when the sleeve 28 is moved inwardly to the position indicated in Figfi pair of conically shaped cams 38 are carried on the surface of the disc 35 facing rearwardly or toward the tap switch M. A pair of cooperating conical cams 39 are carried by the frame H and face outwardly therefrom and cooperate with the cams 38 in the olf position of the tap switch to force the disc 35 out of engagement with the actuating button 26 of the snap switch 25. The disc 35 also carries a pair of conically shaped cams 41 which extend from the opposite surface thereof or toward the panel ill. A pair of brackets 43 are suitably secured to the frame H and carry a pair of sonically shaped cams M disposed to cooperate with the cams 4| to force'the sleeve 28 and the disc 35 to its innermost position to actuate the snap switch 25 when the knob 22 is turned to place the tap switch It in the Glide" position. It will be noted that neither set of cams are effective to determine the position of the sleeve 28 when the knob 22 is positioned in either the Outbound or the Inbound positions. The brackets 43 also carry a pair of blocks 45 which are bored to receive a pair of radially displaceable balls ll, which are biased by springs 48 into an engagement with the sleeve 28. The sleeve 28 is provided with a pair of shallow annular depressions 50 and El separated along the length of sleeve 28 by distance corresponding to the two operative positions thereof. The spring biased balls 47 cooperate with the depressions 50 and ill to provide a detent to maintain the sleeve 23 in either of its operative positions. The blocks 56 are surmounted by a generally annular plate i that serves to increase the rigidity of the assembly,

comprising the brackets 43 and blocks 56.

The switching mechanism also includes a manually operable switch adapted to control the power available from the aircraft power plant. As seen in Figure 1 this switch is designated Engine R. P. M. and is actuated by two buttons, one of which is labeled Efliciency and the other of which is labeled Approach. The details of this switch are best seen in Figure 5. A rockable lever 56 is pivoted in the frame H and has a laterally extending arm 51 adapted to engage the actuating button 59 of a snap switch 60 which is secured to the frame II. A push button 62 is slidable in a bushing 63 which is secured to the frame II. The push button 62 has a pin on its inner end that engages a slot in the left hand end of the lever 56 so that rectilinear movement of the button may be translated into rotary movement of the lever 56. Likewise, a push button 65 is slidable in a bushing 66 and carries a pin that rides in a slot in the right hand end of the lever 56. It will be seen that depression of the button 65 causes engagement of the actuating button 59 of the switch 60 by the arm 57 whereas depression of the button 62 causes the arm 5? to move to the right out of engagement with the actuating button. As best seen in Figure 2, the arm 57 is provided with a laterally extending ear 69 that is adapted to be engaged by an arm ii that extends radially from the disc 35 and is carried thereon by a plate 12 that is secured to one face of the disc. The arm TI is so located with respect to the disc 35 that it engages the ear 6S and moves the lever 56 and the arm 5! to switch actuating position when the disc 35 and the sleeve 28 are turned to the Glide position. It is desirable that the engine should be operating under conditions such that emergency power is available when the aircraft is coming in for a landing. Under blind landing conditions the pilot has many things to occupy his mind and it is desirable that the enine be conditioned to supply maximum power in case of emergency even though the pilot should forget to actuate the switch. By providing the described interlock between the switch that controls engine power and the automatic approach system the proper engine condition is assured.

As described above, the switch 25 may be actuated at the option of the pilot when the tap switch I4 is positioned in either the Outbound or Inbound positions, but it is impossible for the pilot to forget. to actuate the gyroscop controlling switoh 25 when the tap switch M is turned to the Glide position, and the airplane is descending for a landing.

While the invention has been described in connection with a switching mechanism designed for a very specific purpose, it will be understood that it would be equally applicable to other purposes where correlation between the operative positions of two or more switches is desired. It is also contemplated that the invention might be utilized in connection with other than manually operable switches.v The scope of the invention is to be determined only by the appended claims.

I claim as my invention:

1. An electric switching mechanism comprising, a frame, a first switch carried by said frame, a member movable in said frame to move said first switch between a plurality of operative positions, a second switch carried by said frame, a second member movable in said frame to move said second switch between two operative positions, a linkage interconnecting said. first and second members causing said second member to assume a position causing operation of said second switch to one of its operative positions when said first member is moved to a predetermined position, and manually operable means effective to move said second member at other positions of said first member to determine the operative position of said second switch.

2. An electric switching mechanism comprising, a frame, a first switch carried by said frame, a member movable in said frame to move said first switch between three operative positions, a second switch carried by said frame, a second member movable in said frame to move said second switch between two operative positions, and a linkage interconnecting said first and second members and said frame, said linkage actuating said second member to a position corresponding to one operative position of said second switch on movement of said first member to a position corresponding to the first position ofsaid first switch, said linkage actuatin said second member to a position corresponding to the other operative position of said second switch on movement of said first member to a position corresponding to the second position of said first switch, and said linkage having no effect on the operative position of said second member when said first member is moved to the position causing said first switch to assume its third operative position.

3. An electric switching mechanism comprising, a frame, a first member rotatable in said frame, a first switch movable between a plurality of operative positions by angular movement of said first member, a second member rotatable with said first member and slidable axially with respect thereto, a second switch actuated between first and second operative positions by axial movement of said second member, cam means acting between said frame and said second member in one angular position of said members to cause said second member to assume a position to actuate said second switch to its first operative position, and a knob on said second member for manually positioning said second member to move said second switch between its first and second positions at other angular positions of said first member.

4. An electric switching mechanism comprising, a frame, a first member rotatable in said frame, a first switch movable between three op erative positions by rotation of said first me; her, a second member rotatabie with said first member and slidable axially thereon, a second. switch actuated between first and second operative positions by axial movement of said second member, and cam means acting between said frame and said second member in one angular position of said members to move said second member to actuate said second switch to its first operative position, in a second an ular position to permit said second member to be moved axially to actuate said second switch to either of its operative positions, and in a third angular position to move said second member positively to the position in which said second switch is moved to its second operative position.

5. An electric switching mechanism comprising, a frame, a member pivotally mounted in said frame, means on said frame preventing axial movement of said member, a tap switch carried by said frame and actuatable between a plurality of operative positions on a rotation of said memher, a rod slidable axially within a tubular portion of said member, a sleeve slidable axially on an external surface of said member, means extending radially through a lateral opening in said member and interconnecting said rod and said sleeve to cause the axial position of said sleeve to correspond to the axial position of said rod, 21. second switch carried by said frame and having an actuator movable between two operative positions by said sleeve on axial movement thereof, a pair of cooperating cam surfaces carried by said frame and said sleeve causing said sleeve to assume a predetermined axial position when said member is moved to a predetermined angular position, and a knob on said rod for manually positioning said sleeve.

6. An electric switching mechanism comprising, a frame, a member pivotally mounted in said frame, means on said frame preventing axial movement of said member, a tap switch carried by said frame and actuatable between a plurality of operative positions on rotation of said met ber, a rod slidable axially within a tubular portion of said member, a sleeve slidable axially on an external surface of said member, means extending radially through a lateral opening in said member and interconnecting said rod and said sleeve to cause the axial position of said sleeve to correspond to the axial position of said rod, a second switch carried by said frame and having an actuator movable between two operative positions by said sleeve on axial movement thereof, a first pair of cooperating cam surfaces on said frame and said sleeve causing said sleeve to assume one axial position when said member is moved to a first predetermined angular position, a second pair of cooperating cam surfaces on said frame and said sleeve causing said sleeve to assume its other axial position when said member is moved to a second predetermined angular position, and a knob on said rod for manually positioning said sleeve and determining the operative position of said second switch at other angular positions of said member.

7. An electric switching mechanism comprising, a frame, a first member rotatable in said frame, a first switch movable between a plurality of operative positions by angular movement of said first member, a second member rotatable with said first member and slidable axially with respect thereto, a second switch actuated between first and second operative positions by axial movement of said second member, cam means acting between said frame and said second member in one angular position of said members to cause said second member to assume a position to actuate said second switch to its first operative position, a knob on said second member for man ually positioning said second member to move said second switch between its first and second positions at other angular positions of said first member, a third switch carried by said frame, means including a manually operable member for actuating said third switch between first and second operative positions, and an arm projecting radially from said second member and adapted in one angular position of said members to engage said means and actuate said third switch to its first operative position.

8. An electric switching mechanism comprising, a frame, a first member rotatable in said frame, a first control means movable between a plurality of operative positions by angular movement of said first member, a second member rotatable with said first member and slidable axially with respect thereto, a second control means actuated between first and second operative positions by axial movement of said second member, cam means acting between said frame and said second member in one angular position of said members to cause said second member to assume a position to actuate said second control means to its first operative position, and a knob on said second member for manually positioning said second member to move said second control means between its first and second positions at other angular positions of said first member.

9. An electric switching mechanism comprising, a frame, a first switch carried by said frame, a member movable in said frame to move said first switch between a plurality of operative positions, a second switch carried by said frame, a second member movable in said frame to move said second switch between two operative positions, and interlocking means acting on said second member at one position of said first member to cause said second member to assume a position in which said second switch is moved to one of its operative positions, said interlocking means being ineffective to determine the position of said second member at another position of said first member.

GEORGE A. KWASNIEWSKI.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,576,836 Hilsinger, Jr. Nov. 27, 1951 

